Ionic serve doesn't make a new build

All started one month ago. At first the livereload in ionic serve hasn’t worked for me anymore.
Ok, I thought, I could live with that.

Now I wanted to connect Electron and my Ionic Desktop Application.
Like it is described here: https://competenepal.com/ionic2-electron/

But then the ionic serve didn’t reload the new data I have inserted, either in scss, html or ts

What I have done yet:
I thought, it could be something with electron so I removed all the entries in package.json with it and also all the files which had to do with electron.
Then I tried again - still not working. I reinstalled ionic and cordova and still not working. I delete the node-modules. still not working.

Then i made a new project and made ionic serve there. But it looks like it doesn’t even build a new application and just returns the old one.

Best is, if you look at the screenshot from my terminal:

My ionic info:

Can someone help me with this problem?
What can I do to get ionic serve working again, maybe even livereload?
Thanks for all your help in advance

Search here for related issues: https://github.com/ionic-team/ionic-cli/issues

These could match:
https://github.com/ionic-team/ionic-cli/issues/2619
https://github.com/ionic-team/ionic-cli/issues/2602